Use of a thread protector is necessary when your suppressor or other muzzle device is not in use. Backup Tactical specializes in the manufacture of AR-15 thread protectors. Constructed from the strongest firearms grade aluminum alloy and precision CNC machined for a perfect fit, these thread protectors are strong while keeping unwanted ounces off your gun. They aren't just your run of the mill black knurled protector, either. They protect your threads while giving your firearm a custom look.